Lap tray with leg engaging means



Dec. 22, 1953 I. NEWMAN LAP TRAY wrm LEG ENGAGING MEANS Filed June 16, 950

Patented Dec. 22, 1953 UNITED STATES E ATENT OFFICE This invention relates to. trays and in particular to a lap tray which can be firmly held upon a users lap. p

In the ordinary household many situations arise in which food will be served away from the table. The problems thus created for the individual required to balance the tea cup are many, and have been the subject of much humor but of little attempt at solution. The recognition of the situation is substantially universal. but attempts to relieve the distress of the individual subjected to this kind of social. treatment have been absent.

It is, accordingly, a fundamental object of the instant invention to provide a lap tray which will solve the balancing problems accompanying the service of refreshment away from the conventiona], table.

It is a second object of the invention to provide a lap tray which will be useful in holding material on a users lap and will also be compact enough to permit the average hostess to own and store a substantial number thereof.

It is a further object of the invention to provide a lap tray useful for furnishing a convenient surface in the lap of the user.

It is a further object of the invention to provide, a lap tray which takes into account the provision of a substantially level surface at the users lap.

Other objects and advantages of the invention will in part be obvious and in part appear hereinafter.

The invention accordingly comprises, a tray providing a surface and means on thelower side of said tray to clamp the article to a users lap firmly yet with sufiicient resiliency to provide for a moderate amount of movement, which structure is characterized by having a. pair of clamps usable to grasp a users knees, the clamps being holdable or collapsible into a tube. The invention thus comprises a tray having. leveling means and knee clamping means hereinafter to be described, which invention is characterized by the features of construction, combinations, of elements and arrangement of parts to be described in greater detail in conjunction with the accompanying drawings.

In those accompanying drawings:

Figure l is a general illustration of the lap tray in use;

Figure 2 is a front elevation of the tray showing the knee grasping means and the leveling device;

Figure 3 is an elevation of the underside of: the

1 Claim. (Cl. 311-23) 2 tray showing the structure and arrangement of parts thereon;

Figure 4 is a section taken along the line- 4--4. of Figure 2 showing a method of mounting the device on the tray;

Figure 5 is a section taken longitudinally through a typical one of the knee grasping devices;

Figure 6 supplements Figure 5 in showing how the knee grasping device is mounted and can be used;

Figure 7 is a longitudinal section through an alternative form of the device;

Figures 7a and 7b are cross sections through an alternative form of the device;

Figure 8 is a detailed section showing the mounting of the leveling means; and

Figure 9 is a fragmentary front elevation showing the mounting of the leveling means on the device.

Referring back now to Figure 1, It) represents an individual seated with the tray I I fixed in his. lay in a position representing a normal use of the device.

In Figures 1 and 2 there can be seen the various elements making up the tray. Thus I2, I 3, l4 and I5 represent generally L-shaped knee clamping means which are resiliently mounted in essentially tubular units l6, l1, I8 and I9 on the back face of the tray.

Taking into account the fact that in an average sitting position, an individual lap will be inclined slightly forward, the hing-ed leveling means 20 is provided on the bottom surface of the tray. In order to hold the hinged piece firmly in raised or leveling position, fastening means 23 is provided in the form of a small band spring bent to bear on cross bar 24 in the opening 25 of the leveling means. The detail of this struc ture is shown in Figures 8 and 9.

The detailed structure of the knee clamping means is shown in Figure 5, where i l represents the tray and 50 any one of. the tubes mounting the knee clamping device. It should be appar cut that the tube may be a separate piece or it may be formed integrally with the tray itself. The knee clamping piece 5! slides in the tube and carries a boss 52 on the end thereof to which spring 53 is attached. The opposite end of spring 53 is fastened close to the end of tube 5!! to de velop the desired amount of tension and cause the normal position of the knee clamping device to be one in which it is held in position Well in the tube so that the ends thereof do not project out from the edges of the tray. Spring 53 is made short enough to supply the necessary tension to hold the grasping device in the withdrawn po sition shown in Figure 5. For convenience in storage and to assure the retention of the knee clamp 51 in flat position shown in. Figure 3, it is desirable to have the spring 53 also exert a rotational force so that during intervals when the tray is not being used the spring not only retains piece 53 drawn into the tube but also turns it over into the flat storage position shown. This is accomplished by mounting the spring as shown in Figure 6 where a spring 53 is put through the boss 52 in one position and the desired amount of torsional force applied thereto before fastening the other end at 54. In this fashion the nor mal position of grasping device will be in the fiat position for storage. For added convenience, the thickness of the leveling means 25 is made seen that the device is shown in Figure 3 to correspond to the diameter of the tube 5 v so that when the-device is laid flat, no one element on the back face thereof causes the stack to be thrown out of level. The provision of the border border H on its up er face carries the several tubes mounting the knee clamp device on the lower face shown. This embodiment is that in which the tubes constitute separate pieces and are fastened to the back face of the tray. Also appearing in this embodiment is a leveling device and the flat spring mechanism 23 for holding it in position.

in view of the fact that extension of clamping device 5| willcause spring 53 to exert a given amount of tension thereon, it is desirable to overcome this to some extent when the device is extended, and for this purpose a fiat spring arrangement 55 corresponding in structure to that shown as 3 is employed by providing small notches or slight reductions in the diameter of any of the knee holding devices. Upon extension thereof and placement of any one of these under spring 55, the knee clamp device can be heldin a given fixed position.

An alternative embodiment of the knee clamping spring structure is shown in Figure .7 where it represents any one of the tubes mounting a knee clamping device ll, which corresponds to anyone of those shown in Figure 3, as [2, l3, M or 15. Within the tube, knee clamping'device will terminate in an extended piece E2 of diameter reduced from that of the rod itself. Longitudinally aligned alon the extension of reduced diameter are flat spring elements 13 and 'M, etc. Surrounding the extension T2 and thereby forming a compression spring, elements i3 and M, are joined to the extension 12 at their ends i5, i6 and raised to a diameter slightly greater than the inside diameter of the tube. The result is that when the knee clamping device carrying this compression spring structure on the end thereof is inserted in the tube, it forms a close resilient frictionfit and one which permits the withdrawal of the clamping device H to any point and any positioning thereof as desired. The spring structure can be made in a single flat element where the parts 13, it etc. are formed by making slits in the flat piece which is thereafter rolled into a cylinder and mounted on the extension '12. This element is shown in cross section in Figure 711. Thus in Figure 7a the leaves of the compression form of spring attached to '12 and bearing against the tube are shown as a series or" six leaves identified generally as 13 and It. In Figure 7b the variant is one in which the circular spring 73 is a continuous flexible tubular element of somewhat lesser diameter than the tube '10 and which bears against an internal bead it which functions as a detent to hold it in any position.

It willbe understood, of course, that a similar eiiect could be obtained by bending a rod H or its extension '12 in a large radius so as to provide frictional engagement with the inside wall of the tube 72. Also by making rod il a close fit within the tube to provide frictional engagement, a satisfactory result can be achieved.

The operation of the structure should be apparent from the description thereof. It will be substantially as it appears when taken from storage, that is the several knee clamping devices lie fiat against the back of the tray to be used when the leveling means 23 is raised and the several knee clamps extended. The device is then placed on the knees where any further adpjustment can be made. When it is desired to discontinue use, it is removed from the knees and simply by turning the knee clamping elements to the fiat position, the several springs will retract them into the storage positions designed therefor.

It will be apparent that the device has utility as a convenient lap tray for service of foods and refreshment both within the home and for picnic purposes. be served, its utility becomes apparent inthat it provides a convenient level surface which the user can take advantage of for consumption of his refreshment.

Though the invention has been described with only a single embodiment it is apparent from the description that other variations can be made without departing from the spirit or scope of the invention except as limited by the claim.

What is claimed is:

A lap tray comprising a sheet defining an upper and a. lower surface, a plurality of clamping devices mounted on the lower surface thereof, said devices comprising L-shaped members mounted in guide tubes and having outwardly extending portions thereof in an arcuate form, each guide tube also enclosing a spring, one end of which is attached to a clamping device, the other end being attached to a fixed point on the enclosing tube to render the device retractable said lower surface also carrying at each tube a lever resiliently mounted to contact the clamping device and retain it in a given extended position.

IRVING NEWMAN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 527,108 Cooper Oct. 9, 1894 815,200 Moore Mar. 13, 1906 1,008,037 Johnson Nov. '7, 1911 1,436,859 Bush Nov. 28, 1922 1,520,085 Rossiter Dec. 23, 192i 1,555,033 Thweatt Sept. 29, 1925 1,732,520 Leatherrnan Got. 22, 1929 2,054,908 Rich Sept. 15, 1386 2,115,323 Wuest Apr. 26, 1938 2,127,980 Niemann Aug. 23, 1938 2,476,620 Nichols July 19, 1949 FOREIGN PATENTS Number Country Date 322,650 Great Britain Dec. 12, 1929 Similarly, Where large numbers are to 

